The following relates generally to wireless communication, and more specifically to autonomous uplink transmission techniques using shared radio frequency spectrum.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems, (e.g., a Long Term Evolution (LTE) system, or a New Radio (NR) system). A wireless multiple-access communications system may include a number of base stations or access network nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE).
Some wireless systems may enable communication between a base station and a UE over shared or unlicensed radio frequency spectrum bands, or over different radio frequency spectrum bands (e.g., licensed radio frequency spectrum bands and unlicensed radio frequency spectrum bands). When using a shared or unlicensed radio frequency spectrum band, transmitters (e.g., UEs, base stations, or other network access devices) may perform contention-based channel access (e.g., by performing a listen before talk (LBT) procedure) according to contention-based rules that provide for fair channel access to transmitters that wish to use the shared radio frequency spectrum band.
In some cases, a base station may schedule UEs for uplink communications through an assignment or grant of resources. In some cases, a base station may configure a UE to autonomously transmit uplink communications according to an autonomous uplink configuration. In such cases, the base station may not be aware of particular timings for uplink transmissions, due to the autonomous nature of such transmissions and due to the contention-based access to the shared radio frequency spectrum band.